Can JMeter record requests on an application that is developed using Blazor Framework?

Question

Blazor is a free and open-source web framework that enables developers to create web apps using C# and HTML.

Currently on launching the application that is developed with Blazor through JMeter (after providing all the necessary JMeter configurations), the contents of the page are not displayed in UI and nothing is recorded.

Dmitri T Dmitri T · Accepted Answer · 2021-01-06T09:05:16

It depends on the edition and your application implementation, according to Wikipedia:

Five different editions of Blazor apps have been announced.

Blazor Server: These apps are hosted on an ASP.NET Core server in ASP.NET Razor format. Remote clients act as thin clients, meaning that the bulk of the processing load is on the server. The client's web browser downloads a small page and updates its UI over a SignalR connection. Blazor Server was released as a part of .NET Core 3.2 Blazor WebAssembly: Single-page apps that are downloaded to the client's web browser before running. The size of the download is larger than for Blazor Server, depends on the app, and the processing is entirely done on the client hardware. However, this app type enjoys rapid response time. As its name suggests, this client-side framework is written in WebAssembly, as opposed to JavaScript (while they can be used together). Blazor WebAssembly 3.2.0 was released on May 19th, 2020.3

Microsoft plans to release Blazor PWA and Blazor Hybrid editions. The former supports progressive web apps (PWA). The latter is a platform-native framework (as opposed to a web framework) but still renders the user interface using web technologies (e.g. HTML and CSS). A third, Blazor Native – platform-native framework that renders a platform-native user interface – has also been considered but has not reached the planning stage.2

With JMeter's HTTP(S) Test Script Recorder you can only capture and record HTTP and HTTPS traffic, SignalR won't be recorded, you will need to

capture the traffic using an external sniffer tool like Fiddler or Wireshark
identify which network protocol(s) are in scope
find the relevant Sampler or JMeter Plugin or Java client library for this protocol(s) and replicate the client traffic

For example if you need to test Blazor Server based application most probably it will assume SignalR communication channel, in its turn most probably it will use WebSockets so you will need WebSocket Samplers plugin

Can JMeter record requests on an application that is developed using Blazor Framework?

1 Answers